摘要
正交异性钢箱梁为现代大跨度桥梁所广泛采用,但其属于薄壁结构,在大轴力作用下稳定问题较为突出。针对U形加劲板在轴心受压作用下的稳定承载力计算提出简化模型,以加劲板母板为研究对象,将加劲肋简化为弹性约束边界条件,运用瑞利-里兹法推导加劲板的弹性屈曲临界荷载计算公式。将理论解与ANSYS数值解进行对比,结果吻合较好,对于算例中的U形加劲板,非加载边考虑弹性约束,比四边简支约束条件时临界屈曲荷载增加16.25%,该计算模型比四边简支模型具有更高的精度。基于计算公式进一步讨论了弹性约束刚度与屈曲系数、加劲肋几何尺寸及加劲肋母板宽厚比的关系,弹性刚度K均随着U肋尺寸的增加而增加,增加U肋腹板高度比增加顶板宽度更有效。当弹性刚度为常数时(非加载边为弹性约束),屈曲系数随宽厚比的增大而增大。研究结果可为U形加劲板的设计提供参考。
Orthotropic steel box girders are widely used in modern long-span bridges which belong to thin-walled structures, and the stability problem is a major issue under strong axial forces.In this paper, a simplified calculation model is proposed for the stability of U-rib stiffened plate under axial compression.The U-rib is simplified as an elastic constraint boundary condition, and the calculation formula of elastic buckling critical load of stiffened plate is derived by Rayleigh-Ritz method.The theoretical solution is compared with the numerical solution of ANSYS,and the results are in a good agreement.For the case of U-rib stiffened plate in this paper, the elastic constraint is considered at the non-loading side, which is 16.25% higher than the critical buckling load when the four sides are simply supported.This calculation model has a better accuracy than the four-side simple supported model.Based on the calculation formula, the relationship between the elastic restraint stiffness and the buckling coefficient, the geometric dimension of the U-rib and the width-thickness ratio of the stiffener base plate is further discussed.The elastic stiffness K increases with the increase of the size of U-rib, and the increase of the U-rib web height is more effective than the increase of the roof width.When the elastic stiffness is constant(the non-loaded edge is elastic rotational constraint),the buckling coefficient increases with the increase of the width-thickness ratio.This research results can provide a reference for the design of U-rib stiffened plate.
作者
王飞
申磊
赵卓
张哲
WANG Fei;SHEN Lei;ZHAO Zhuo;ZHANG Zhe(School of Civil and Transportation Engineering,Ningbo University of Technology,Ningbo 315211,China;Engineering Research Center of Industrial Construction in Civil Engineering of Zhejiang Province,Ningbo University of Technology,Ningbo 315211,China;Henan Provincial Academy of Building Research,Zhengzhou 450053,China;School of Civil Engineering,Zhengzhou University,Zhengzhou 450001,China)
出处
《建筑钢结构进展》
CSCD
北大核心
2021年第12期56-64,共9页
Progress in Steel Building Structures
基金
浙江省自然科学基金(LQ20E080012)
宁波市科技创新2025重大专项(2019B10076)。
关键词
桥梁工程
正交异性钢箱梁
U形加劲板
稳定承载力
弹性约束
瑞利-里兹法
bridge engineering
orthotropic steel box girder
U-rib stiffened plate
stable capacity
elastic constraint
Rayleigh-Ritz method
